In a pneumatic yarn splicing apparatus, yarn ends to be spliced are untwisted to separate fibers of the yarn ends, the yarn ends to be spliced are doubled in this fiber-separated state, compressed air is applied to the doubled portion and twisting or torsion is caused in the doubled portion by swirling air streams, and the fibers of both the yarn ends are entangled with one another to integrate both the yarn ends with each other, whereby the splicing operation is accomplished.
This process is illustrated in the specification of U.S. Pat. No. 4,240,247 and U.S. Pat. No. 4,263,775.
In the above-mentioned splicing process, a control nozzle for sucking the yarn ends and jetting a jet stream to the yarn ends to untwist the yarn ends and a splicing member for applying a jet stream to the yarn ends to twist them are independently arranged according to the conventional technique. Especially, since the control nozzle bends the end of yarn sucked in the splicing apparatus in a direction intersecting the yarn-sucking direction to untwist the yarn end and draws out the untwisted yarn end from the control nozzle again, there is often formed a portion in which opening or separation of fibers of the yarn end is insufficient.
Furthermore, since the splicing member supports only a limited part of the yarn end to be spliced but does not support entirely the yarn to be processed, it is considered that when the spliced portion is twisted by applying a jet stream thereto, slackening of fibers is caused between the supported part and the unsupported part.
Moreover, the foregoing untwisting and entangling operations are carried out in a groove in which the yarn ends are contained, and in order to uniformalize the lengths of the untwisted yarn ends, it is necessary that a cutter disposed outside the groove should be actuated to cut the yarn ends. Accordingly, the time required for the splicing operation is inevitably prolonged by the time for operating the cutter, and provision of the cutter is not preferred from the viewpoint of the operation efficiency. Still further, a cam mechanism and other members should be necessary if this cutter is disposed.